Damper control

ABSTRACT

In the preferred form, there is provided a horizontal duct through a vertical partition wall between compartments of a refrigerator. A plastic damper control unit is slidably mounted in this duct and has a scoop-type vane projecting into the air stream flowing from the evaporator compartment for diverting a proportion of the circulating air through the horizontal duct in the partition wall to the compartment on the opposite side of the wall. The opposite side of the wall is provided with a rotary control knob for moving the scoop vane to various positions providing rates of flow in proportion to the position of the knob. The damper control is a part of a unit which includes a thermostat control switch having a thermosensitive bulb extending into the air stream of the air discharged from the duct for controlling the operation of the refrigerating system and the temperature of the evaporating means.

United States Patent [72] Inventor Roger M. Boor Dayton, Ohio [21] Appl. No. 7,498 [22] Filed Feb. 2, 1970 [45] Patented Dec. 28, 1971 [73] Assignee General Motors Corporation Detroit, Mich.

[54] DAMPER CONTROL 4 Claims, 4 Drawing Figs.

[52] U.S. Cl 62/408, 62/187,62/4l9 [51] Int. Cl F25d 17/04 [50] Field of Search 62/408, 187, 419

[56] References Cited UNITED STATES PATENTS 3,084,520 4/1963 Jacobs... 62/408 3,093,981 6/1963 OGrady. 62/408 .2o 1 t',3o/ 21 Simer ..#2 /10 I 3 ,248,894 Harbour;

3,522,712 8/1970 Carl 62/419 Primary Examiner-William .l. Wye AttorneysWilliam S. Pettigrew, Frederick M. Ritchie and Edward P. Barthel ABSTRACT: In the preferred form, there is provided a horizontal duct through a vertical partition wall between compartments of a refrigerator. A plastic damper control unit is slidably mounted in this duct and has a scoop-type vane projecting into the air stream flowing from the evaporator compartment for diverting a proportion of the circulating air through the horizontal duct in the partition wall to the compartment on the opposite side of the wall. The opposite side of the wall is provided with a rotary control knob for moving the scoop vane to various positions providing rates of flow in proportion to the position of the knob. The damper control is a part of a unit which includes a thermostat control switch having a thermosensitive bulb extending into the air stream of the air discharged from the duct for controlling the operation of the refrigerating system and the temperature of the evaporating means.

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BY foyer Z7? $2902 dazzm ATTORNEY DAMPER CONTROL This invention pertains to two-compartment refrigerators in which a portion of the air being circulated in one of the compartments is diverted through the partition wall into another compartment.

To simplify the control systems and arrangements in frost free refrigerators, it has been customary to divert a portion of the circulating air in the below freezing compartment to the above freezing compartment. The proportioning of the circulating air has been obtained through the use of a manually controlled damper in the lower cost models. However, it has been found that such manual dampers have not diverted the air in proportions corresponding to the position of the knob or control device. Furthermore, such damper have been relatively expensive to manufacture and assemble.

It is an object of this invention to provide a damper control for two-temperature two-compartment refrigerators in which the volume of air diverted from the circulation in the colder compartments to the warmer compartments is substantially in accord with the position of the manually adjustable control device located in the warmer compartments.

It is another object of this invention to provide a control unit embodying a damper, a duct and a control device for the damper which is simple, inexpensive, easy to assemble and remove and which is reliable and substantially free of moisture or frost problems.

Further objects and advantages of the present invention will be apparent from the following description, reference being had to the accompanying drawings, wherein preferred embodiments of the present invention are clearly shown.

In the drawings:

FIG. 1 is a front view of a refrigerator having side by side compartments with the doors removed to show the interior thereof;

FIG. 2 is an enlarged view of the damper and switch controls shown in the upper portion of FIG. 1;

FIG. 3 is a fragmentary vertical sectional view taken along the lines 3-3 of FIGS. 1 and 2; and

FIG. 4 is a fragmentary horizontal sectional view taken along the lines 4-4 of FIGS. 1 and 2.

Referring now to the drawings and more particularly to FIG. 1, there is shown a refrigerator having top and bottom walls 22 and 24, sidewalls 26 and rear wall 28. The interior of the refrigerator is divided by an upright insulated partition wall 30 which divides the interior into a freezing compartment 32 located on the left side of the partition wall 30 and an above freezing compartment 34 located on the right side of the partition wall 30.

Located in a vertical air cooling duct 36 on the lower rear wall of the compartment 32 is a vertical finned refrigerant evaporator 38 which is operatively connected to an electric motor driven compression refrigeration system, not shown. The bottom of the duct 36 is open but is provided with a drain pan 40 beneath it for collecting the defrost water from the evaporator 38 during any defrosting thereof. Air is drawn from the above freezing compartment 34 through a passage 42 in the lower portion of the partition wall into the bottom of the cooling duct 36 adjacent the bottom of the evaporator 38. A centrifugal fan 44, located in a suitable fan housing 46, has its inlet connecting with the duct 36 above the evaporator 38 and discharges a substantial portion of its air through an outlet 48 above it into the midportion of the freezing compartment 32. The remaining portion of the air circulated by the fan 44 is discharged through a second upwardly extending duct 50 for discharge through the top outlet 52 of the duct 50 into the compartment 32. This dual outlet arrangement for the fan 44 assures more uniform maintenance of low temperatures from the top to the bottom of the freezing compartment 32.

According to this invention, to provide a suitable control of the temperatures in the compartments 32 and 34, there is provided a scooping manual damper control arrangement 54 by which the amount of cold air delivered from the duct 50 to the compartment 34 is selected in accordance with the adjustment of the knob 80 in the compartment 34. As is better shown in FIGS. 2-4, the vertical partition wall 30 is provided with a plastic transition duct member 58 adjacent the inner section of the rear wall 28 and the top wall 22. This transition duct member includes a horizontal rectangular plastic sleeve extending between the compartments 32 and 34. The partition wall 30 also includes sheet plastic surface wall members 60 and 62 between which there is cast plastic foam insulation 64 which encloses the transition duct 58.

For ease of assembly, the damper control unit is slidably mounted in the sleeve of the transition duct 58. This damper control unit 54 includes a horizontal duct slidably mounted within the transition duct 58 which is formed of a front member 66 forming the front and top and bottom walls of the duct and a rear member 68 forming the rear wall of the duct which is connected to the front member 66 by a tongue and groove arrangement to prevent leakage of air. The rear wall is provided with a hollow boss 70 providing a rear bearing for the damper control shaft 72 which includes an intermediate disc-shaped portion 74 and a front shaft extension 76 extending through a bearing 78 in the front member 66. The front extension 76 is provided with a removable control knob 80 which cooperates with suitable position indications on the plastic front cover 82.

The disc-shaped portion 74 is provided with an eccentrically located pin 84 projecting into the interior of the duct formed by the front and rear walls 66 and 68. This pin 84 is adapted to project through the bearing link in one end of a connecting rod or link 86. The opposite end of this rod or link 86 is provided with a loop shaped portion fitting over the pin 88 projecting from the adjacent side of a pivoted vane damper 90. This vane 90, at its upper end, is provided with oppositely projecting pivot pins 92 which project within bearing apertures provided in the adjacent portions of the front and rear members 66 and 68 of the slidably mounted duct. The walls of the members 66 and 68 extend into the compartment 32 and are provided on the projecting end with curved edges 94 which fit the adjacent curved surface of the pivoted vane damper which is curved in a manner similar to a portion of a cylinder extending downwardly from the pivot pins 92.

The eccentric pin 84 is offset from the axis of the shaft 72 about one-third the distance of the pins 88 from their pivot pin 92. The connecting rod or link 86 is of such a length that when the damper 90 is in its closed position the eccentric pin 84 will be rotated to a position of about 45 to the right. With this arrangement, when the eccentric pin and the shaft 72 are turned in the counterclockwise direction as viewed in FIGS. 1 and 2, the scoop-shaped vane or damper 90 will be opened in gradually increasing amounts so that the air circulation is increased in amounts substantially proportional to the amount that the knob 80 is turned in a counterclockwise direction from its fully closed position. This results from the amount of movement provided to the vane 90 and also the position and curvature of the vane 90 so that it acts as a scoop projecting into the air duct 50 to scoop and divert increasing amounts of the circulating air from the duct 50 into the transverse duct formed by the front and rear members 66 and 68. The proportion of diverted air is substantially in proportion to the movement of the control knob 80 away from the closed position.

All the ducts, the fan, the link, the shafts 72 and 76 and the disc 74 are of suitable plastic such as ABS (acrylic-butadienestyrene) copolymer so that no substantial amount of heat escapes through them from the compartment 34 to the compartment 32 thereby preventing sweating and other objectionable results. These plastic partitions also require no lubrication and will not corrode in the presence of moisture and will operate without sticking and a minimum of wear under wide variations of temperatures. Other plastics such as acetal, polyamides, polyethylene and polypropylene resins may be used, if desired.

The cover 82 is extended downwardly below the knob 80 and supports the thermostatic control switch 98 through the use of screws 99. This thermostatic control switch is connected in series with the electrical conductors 121 which pass through an insulation bushing 123 and connect in series with the motor compressor unit, not shown. This bushing 123 extends through the rear wall. The thermostatic control switch 98 is provided with a thermostatic bulb in the form of a capillary tube 125 which projects into the circulating air at the top of the compartment 34. This switch has a relatively low temperature differential for maintaining the compartment 34 at about 36 F. The thermostatic control switch 98 and the capillary tube 125 are insulated from the duct members 66 and 68 by a molded piece of polystyrene beads 127. The thermostatic control switch 98 is provided with an adjustable control knob 129 which connects to the adjusting shaft projecting through the cover 82. The knob 129 cooperates with suitable indications on the cover 82.

The cover 82 is fastened in place by the screw 131 which threads into the rear wall 28 of the compartment 34. With this arrangement the entire damper control thermostatic control switch including the duct, insulation, controls and cover, may be assembled as a unit before installation in the refrigerator cabinet. All that is necessary to assemble it to the cabinet is to make the proper connections for the electrical conductor 12] and to slide the left portion of the duct comprising the members 66 and 68 together with the damper 90 through the sleeve of the transition duct 58 until the adjacent side of the cover 82 rests against the sheet 62 of the wall 30 and the duct 58. The unit then is fastened by the screw 131 into the rear wall. This provides an arrangement wherein the adjustment of the knob 56 provides a corresponding change in the amount of air diverted through the partition wall 30. This is all accomplished by plastic members which may be readily molded and assembled as aunit before installation can be attained.

While the embodiments of the invention as herein disclosed constitute preferred forms, it is to be understood that other forms might be adopted.

lclaim:

1. A refrigerator including insulated outer enclosing walls enclosing a space, a partition wall extending within said space between said outer walls to divide said space into first and second compartments, means comprising refrigerant evaporating means and duct means for circulating cold air in said first compartment, said partition wall being provided with a passage extending from said first compartment to said second compartment, wherein the improvement comprises a movable damper having pivot means adjacent the entrance to said passage on the side opposite where the circulation of air approaches said passage and being curved away from said passage substantially from said pivot means to its opposite extremity to form a scoop for scooping a portion of said circulating air into said passage substantially in proportion to its angular position relative to said passage.

2. A refrigerator including insulated outer enclosing walls enclosing a space, a partition wall extending within said space between said outer walls to divide said space into first and second compartments, means comprising refrigerant evaporating means and duct means for circulating cold air in said first compartment, said partition wall being provided with a passage extending from said first compartment to said second compartment, wherein the improvement comprises a movable damper having pivot means adjacent the entrance to said passage on the side opposite where the circulation of air approaches said passage and being curved away from said passage substantially from said pivot means to its opposite extremity to form a scoop for scooping a portion of said circulating air into said passage substantially in proportion to its angular position relative to said passage, said passage adjacent said damper having opposite walls terminating in edges having substantially the same curvature as said damper.

3. A refrigerator including insulated outer enclosing walls enclosing a space, a partition wall extending within said space between said outer walls to divide said space into first and second compartments, means comprising refrigerant evaporating means and duct means for circulating cold air in said first compartment, said partition wall being provided with a passage extending from said first compartment to said second compartment, wherein the improvement comprises second duct means extending through and mounted in said passage, damper means operably connected to said second duct means adjacent said first compartment for controlling airflow through the second duct means, said second duct means having an extension extending into said second compartment, adjustable control means mounted upon said extension accessible in said second compartment, and operable connecting means connecting said adjustable control means and said damper means for moving said damper means to selective positions in accordance with the adjustment of said control means.

4. A refrigerator including insulated outer enclosing walls enclosing a a partition wall extending within said space between said outer walls to divide said space into first and second compartments, means comprising refrigerant evaporating means and duct means for circulating cold air in said first compartment, said partition wall being provided with a passage extending from said first compartment to said second compartment, wherein the improvement comprises second duct means extending from said second compartment through said passage to said first compartment, a movable damper and pivot means pivotally connecting said damper to said second duct means adjacent said first compartment on its lee side relative to the circulating air, said damper extending from said pivot means into the circulating air for scooping a portion of said circulating air for flow through said second duct means, said duct means having an extension extending into said second compartment, an adjustable control means mounted upon said extension accessible in said second compartment, and operable connecting means extending through said second duct means operably connecting said control means and said damper for moving said damper to selective angular positions about said pivot means in accordance with the adjustment of said control means to scoop selected portions of said circulating air for flow through said second duct means. 

1. A refrigerator including insulated outer enclosing walls enclosing a space, a partition wall extending within said space between said outer walls to divide said space into first and second compartments, means comprising refrigerant evaporating means and duct means for circulating cold air in said first compartment, said partition wall being provided with a passage extending from said first compartment to said second compartment, wherein the improvement comprises a movable damper having pivot means adjacent the entrance to said passage on the side opposite where the circulation of air approaches said passage and being curved away from said passage substantially from said pivot means to its opposite extremity to form a scoop for scooping a portion of said circulating air into said passage substantially in proportion to its angular position relative to said passage.
 2. A refrigerator including insulated outer enclosing walls enclosing a space, a partition wall extending within said space between said outer walls to divide said space into first and second compartments, means comprising refrigerant evaporating means and duct means for circulating cold air in said first compartment, said partition wall being provided with a passage extending from said first compartment to said second compartment, wherein the improvement comprises a movable damper having pivot means adjacent the entrance to said passage on the side opposite where the circulation of air approaches said passage and being curved away from said passage substantially from said pivot means to its opposite extremity to form a scoop for scooping a portion of said circulating air into said passage substantially in proportion to its angular position relative to said passage, said passage adjacent said damper having opposite walls terminating in edges having substantially the same curvature as said damper.
 3. A refrigerator including insulated outer enclosing walls enclosing a space, a partition wall extending within said space between said outer walls to divide said space into first and second compartments, means comprising refrigerant evaporating means and duct means for circulating cold air in said first compartment, said partition wall being provided with a passage extending from said first compartment to said second compartment, wherein the improvement comprises second duct means extending through and mounted in said passage, damper means operably connected to said second duct means adjacent said first compartment for controlling airflow through the second duct means, said second duct means having an extension extending into said second compartment, adjustable control means mounted upon said extension accessible in said second compartment, and operable connecting means connecting said adjustable control means and said damper means for moving said damper means to selective positions in accordance with the adjustment of said control means.
 4. A refrigerator including insulated outer enclosing walls enclosing a a partition wall extending within said space between said outer walls to divide said space into first and second compartments, means comprising refrigerant evaporating means and duct means for circulating cold air in said first compartment, said partition wall being provided with a passage extending from said first compartment to said second compartment, wherein the improvement comprises second duct means extending from said second compartment through said passage to said first compartment, a movable damper and pivot means pivotally connecting said damper to said second duct means adjacent said first compartment on its lee side relative to the circulating air, said damper extending from said pivot means into the circulating air for scooping a portion of said circulating air for flow through said second duct means, said duct means having an extension extending into said second compartment, an adjustable control means mounted upon said extension accessible in said second compartment, and operable connecting means extending through said second duct means operably connecting said contRol means and said damper for moving said damper to selective angular positions about said pivot means in accordance with the adjustment of said control means to scoop selected portions of said circulating air for flow through said second duct means. 